WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.
Synology DiskStation Manager - DiskStation Manager is a data storage platform that comes with a completely private collaboration suite.
TreeSize - TreeSize tells you where precious disk space has gone to.
CTERA - CTERA is the global leader in edge-to-cloud file services.
SpaceSniffer - SpaceSniffer is a freeWare (donations are welcome) and portable tool application that lets you understand how folders and files are structured on your disks.
Nutanix - Nutanix is a virtualized datacenter platform that provides disruptive datacenter infrastructure solutions for implementing enterprise-class.